package com.sky.service.impl;

import com.sky.context.BaseContext;
import com.sky.dto.ShoppingCartDTO;
import com.sky.entity.Dish;
import com.sky.entity.Setmeal;
import com.sky.entity.ShoppingCart;
import com.sky.mapper.DishMapper;
import com.sky.mapper.SetmealMapper;
import com.sky.mapper.ShoppingCartMapper;
import com.sky.service.ShoppingCartService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.util.List;

@Service
@Slf4j
public class ShoppingCartServiceImpl implements ShoppingCartService {

    @Autowired
     private ShoppingCartMapper shoppingCartMapper;

    @Autowired
    private DishMapper dishMapper;

    @Autowired
    private SetmealMapper setmealMapper;

    /**
     * 添加购物车
     * @param shoppingCartDTO
     */
    public void addShoppingCart(ShoppingCartDTO shoppingCartDTO) {
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);
        //设置用户id
        Long userId = BaseContext.getCurrentId();
        shoppingCart.setUserId(userId);

        // 判断当前商品是否在购物车中
        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);

        // 如果已经存在，则增加数量
        if (list != null && list.size() > 0) {
            ShoppingCart cart = list.get(0);
            cart.setNumber(cart.getNumber()+1);
            shoppingCartMapper.updateNumberById(cart);
        }
        // 如果不存在，则添加到购物车，数量默认为1
        else {
            // 判断当前添加到购物车的是套餐还是菜品
            Long dishId = shoppingCartDTO.getDishId();
            if (dishId != null) {
                //添加到购物车的是菜品
                Dish dish = dishMapper.getById(dishId);
                shoppingCart.setName(dish.getName());
                shoppingCart.setImage(dish.getImage());
                shoppingCart.setAmount(dish.getPrice());
            }else {
                //添加到购物车的是套餐
                Long setmealId = shoppingCartDTO.getSetmealId();
                Setmeal setmeal = setmealMapper.getById(setmealId);
                shoppingCart.setName(setmeal.getName());
                shoppingCart.setImage(setmeal.getImage());
                shoppingCart.setAmount(setmeal.getPrice());
            }
            shoppingCart.setNumber(1);
            shoppingCart.setCreateTime(LocalDateTime.now());
            shoppingCartMapper.insert(shoppingCart);
        }
    }

    /**
     * 查看购物车
     * @return
     */
    public List<ShoppingCart> showShoppingCart() {
        Long userId = BaseContext.getCurrentId();
        ShoppingCart shoppingCart = ShoppingCart.builder()
                .userId(userId)
                .build();
        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);
        return list;
    }

    /**
     * 清空购物车
     */
    public void cleanShoppingCart() {
        Long userId = BaseContext.getCurrentId();
        shoppingCartMapper.deleteByUserId(userId);
    }

    /**
     * 删除购物车中一个商品
     * @param shoppingCartDTO
     */
    public void subShoppingCart(ShoppingCartDTO shoppingCartDTO) {
         ShoppingCart shoppingCart = new ShoppingCart();
         BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);
         //设置用户id
         Long userId = BaseContext.getCurrentId();
         shoppingCart.setUserId(userId);

         // 判断当前商品是否在购物车中
         List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);

         // 如果已经存在，则减少数量
         if (list !=null &&list.size() > 0){
             ShoppingCart cart = list.get(0);
             if (cart.getNumber()>1){
                 cart.setNumber(cart.getNumber()-1);
                 shoppingCartMapper.updateNumberById(cart);
             }else {
                 // 如果数量为1，则从购物车中删除该商品
                 shoppingCartMapper.deleteById(cart.getId());
             }
         }
    }
}
